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Scientist Investigate A Brand New Form of Matter: Time Crystals (sciencealert.com)

The discovery of "non-equilibrium matter" could re-write the rules of physics. Long-time Slashdot reader jasonbrown quotes ScienceAlert: For months now, there's been speculation that researchers might have finally created time crystals — strange crystals that have an atomic structure that repeats not just in space, but in time, putting them in perpetual motion without energy. Now it's official — researchers have just reported in detail how to make and measure these bizarre crystals. And two independent teams of scientists claim they've actually created time crystals in the lab based off this blueprint, confirming the existence of an entirely new form of matter.
Both teams -- one at Harvard and the other at the University of Maryland -- have submitted their findings to peer-reviewed publications, according to the article, and "the fact that two separate teams have used the same blueprint to make time crystals out of vastly different systems is promising."

14 of 242 comments (clear)

  1. The article claims crystals are motionless by fredrated · · Score: 3, Interesting

    in their ground state.

    Usually when a material is in ground state, also known as the zero-point energy of a system, it means movement should theoretically be impossible, because that would require it to expend energy.

    However, that would violate quantum electrodynamics, because then you would know the atoms exact momentum and location.
    ???

  2. 'twice the period'? by Rick+Schumann · · Score: 5, Interesting

    The two lasers that were periodically nudging the ytterbium atoms were producing a repetition in the system at twice the period of the nudges, something that couldn't occur in a normal system.

    When they're saying 'twice the period of the nudges', do they mean twice the frequency of the nudges, or twice the duration of the nudges? What I'm after here is, is whether or not they're actually implying that there's more energy coming out of this than is being put into it, and by the way unless I'm totally misreading it, it sounds like this isn't 'perpetual motion' at all, not in the sense I think of 'perpetual motion', because they have to 'nudge' it with a pulse from a laser to cause this effect to occur -- unless what I'm missing here, is that all they have to do is 'nudge' it once, and it starts a self-sustaining oscillation? Even if it's self-sustaining once started, isn't it then in a state of equilibrium regardless, and any attempt to tap into the energy of that oscillation would cause it to stop?

    1. Re:'twice the period'? by Rick+Schumann · · Score: 3

      I did, jackass, and the physics is over my head, so we're discussing it here. If you have nothing of value to add to the conversation then shove off.

  3. Re:Sounds like bullshit by Anonymous Coward · · Score: 5, Informative

    Smarter people than you say otherwise:

    Time crystals may sound dangerously close to a perpetual motion machine, but it is worth emphasizing one key difference: while time crystals would indeed move periodically in an eternal loop, rotation occurs in the ground state, with no work being carried out nor any usable energy being extracted from the system. Finding time crystals would not amount to a violation of well-established principles of thermodynamics.

  4. Re:Practical Uses? by ClickOnThis · · Score: 4, Insightful

    While cool i agree, and i can see perhaps some esoteric use beyond basic research, what sort of practical day-to-day use for the common man would there be?

    Quite likely, it's too early to tell.

    There is a story, perhaps apocryphal or misattributed, of then-prime-minister Benjamin Disraeli visiting Michael Faraday's lab, and asking Faraday "what use is electricity?" Faraday replied: "What use is a new-born baby?"

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  5. Can not get energy out by gurps_npc · · Score: 4, Informative

    Perpetual motion machines are allowed by the laws of physics. The galaxy is one for example, it perpetually rotates effectively forever, and by definition beyond what we can measure.

    What IS impossible, is to remove energy from the system. If you do that, any machine stops, eventually, unless you add it back in somehow.

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    excitingthingstodo.blogspot.com
  6. Re:Sounds like bullshit by ClickOnThis · · Score: 5, Informative

    Smarter people than you say otherwise:

    Time crystals may sound dangerously close to a perpetual motion machine, but it is worth emphasizing one key difference: while time crystals would indeed move periodically in an eternal loop, rotation occurs in the ground state, with no work being carried out nor any usable energy being extracted from the system. Finding time crystals would not amount to a violation of well-established principles of thermodynamics.

    This. Mod parent up.

    Quantum-mechanical systems in their ground state cannot radiate energy, because they are already in their lowest possible energy-state.

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  7. Re:But it's not even April 1st by K.+S.+Kyosuke · · Score: 4, Insightful

    It sounds even more like a name of a classic Dr Who episode. ;)

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    Ezekiel 23:20
  8. Re:Practical Uses? by Harold+Halloway · · Score: 4, Insightful

    The one I know, also likely to be apocryphal, is where William Gladstone, then Chancellor of the Exchequer, asked the same question. Faraday's reputed reply was, "Why, sir, there is every probability that you will soon be able to tax it."

  9. Re:Uh, so what? by JustOK · · Score: 4, Funny

    Newton wasn't a lawyer.

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    rewriting history since 2109
  10. Re:Sounds like bullshit by mikael · · Score: 3, Informative

    What if something were so tightly packed that it started absorbing neutrinos and other particles that would normally travel straight through regular matter?

    Helium-4 seems to do something strange when cooled to a super-liquid - it's just not possible to cool down into a solid because the kinetic energy exceeds the electron bond strengths.

    https://phys.org/news/2009-05-...

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  11. Re:But it's not even April 1st by Darinbob · · Score: 4, Funny

    Timey Wimey Crystals.

  12. Re:Sounds like bullshit by quenda · · Score: 4, Funny

    Attempting to read the article made me feel dumb.
    So I read the comments, and now feel like a genius.

  13. Re:Sounds like bullshit by gweihir · · Score: 3, Insightful

    And there the problem starts. It is fascinating to see how much deeply stupid people are around here that do not even understand how limited their understanding is. The current models for Quantum Mechanics are not truth. They are rough approximations and, if history is any indicator, quite a few things presented by the press as "truth" in there will turn out to have exceptions and inaccuracies. The other problem is that actual observation is now down to indirections of indirections and only mathematical models try to explain what is actually happening there. These models could easily be way off with the lack of quality in th experimental validation.

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